Improvement in piano sounding-boards



UNITED STATES CHRISTIAN F.

PATENT OFFICE.

T. STEINWAY, OF NEW YORK, N. Y., ASSIGNOL.- TO Hlilzllilliif', WILLIAMSTEINWAY, AND ALBERT STEINWAY.

MPRQl/EMENT lN PIANO SOUNDINGSBQARDS.

Specification forming part of Letters Patent No. 135,857, dated February1l, 1873.

,To all ywhom it may concern:

Be it known that I, GHRIsTrAN FRIEDRICH THEoDoR S'rErNwAv, of the city,county, and State of New York, have invented a new and usefulImprovement in Sounding-Boards for Piano-Fortes; and I do hereby declarethe following to be a full, clear, and exact description thereof7 whichwill enable those skilled in the art to make and use the same, referencebeing had to the accompanying drawing forming part of, thisspecification, in which drawing- Figure l represents a longitudinalvertical section. of my invention. Fig. 2 is an inverted plan of thesame.

Similar letters indicate corresponding parts.

rJDhis invention consists in the arrangement of one or more strips ofhardwood in the body of the soft-wood bars or ribs of the soundingboardof a piano-forte in such a manner that the sounding-board is preventedfrom settling down, and the tone of the piano-forte constructed withthis improved sounding-board is not liable to break or to change itscharacter under the most powerful touch.

In the drawing, the letter A designatesthe soundingboard of a pianoforte7 which is strengthened by ribs or bars B secured t0 its undersurface. These ribs cross the libers of the sounding-board, and they areinvariably sawed from boards or planks of spruce or pine wood, so thattheir fibers do not usually eX- tend from end to end in unbroken lines.A sounding-board constructed with the ordina-ry ribs is liable to settledown under the weight and tension of the strings, and the tone of apiano-forte provided with such a soundingboa-rd is liable to break downor to change its character under the touch of a powerful player.

rhese disadvantages I have successfully overcome by inserting into eachof the ribs E one or more strips, a, of hard wood, said ribs beingprovided with grooves for the reception of the hard-wood strips. Thesegrooves eX- tendthroughout the entire length of the ribs, and theyterminate at the usual chamfers l) at the ends of said ribs. The stripsof hard wood are so cut that their bers extend from end to end inunbroken lines, and by combining them with the ribs B the sounding-boardis enabled to withstand effeetually the pressure of the strings, itsvibrating power is in creased, it is prevented from settling down, itdiffuses and transmits the vibrations to all parts of thesounding-board, and the tone of a piano -forte constructed with myimproved sounding-board will not break or change its character under themost powerful touch.

Hard wood, when glued into a groove in the soft-wood rib of asounding-board, contracts a little more or less than the soft wood,since when it is moistened by the glue it expands, and as it dries itcontracts; and by this contraction the sounding-board is slightly bentupward, so that it is capable to resist the tension and weight of thestrings.

I am aware that the bars of sounding-boards ot' pianos have beenstrengthened by inserting a strip of iron within a groove or kerf; suchis not claimed, as it is not my invention; but

Vvhat I claim as new, and desire to secure by Letters Patent, is-N Theemployment of one or more strips of hard wood inserted into the ribs Bof the sounding-board of a piano-forte, substantially in the manner andfor the purpose herein shown and described.

C. F. TH. STEIN WAY.

Witnesses Tro. STEVENsoN, RW. HABE.

